X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/disorder/blobdiff_plain/763d5e6ad88ef3ba1cd1d7742d060e4f1e54c6b8..8ab2aa9fd51a89e06d92a4f7c3792aaa4a08cc71:/lib/hex.c

diff --git a/lib/hex.c b/lib/hex.c
index bd4774a..efe8425 100644
--- a/lib/hex.c
+++ b/lib/hex.c
@@ -1,41 +1,49 @@
 /*
  * This file is part of DisOrder
- * Copyright (C) 2004, 2005 Richard Kettlewell
+ * Copyright (C) 2004, 2005, 2007-9, 2013 Richard Kettlewell
  *
- * This program is free software; you can redistribute it and/or modify
+ * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
+ * the Free Software Foundation, either version 3 of the License, or
  * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
- * USA
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+/** @file lib/hex.c @brief Hexadecimal encoding and decoding */
 
-#include <config.h>
-#include "types.h"
-
-#include <stdio.h>
-#include <string.h>
+#include "common.h"
 
 #include "hex.h"
 #include "mem.h"
 #include "log.h"
+#include "printf.h"
 
+/** @brief Convert a byte sequence to hex
+ * @param ptr Pointer to first byte
+ * @param n Number of bytes
+ * @return Allocated string containing hexdump
+ */
 char *hex(const uint8_t *ptr, size_t n) {
   char *buf = xmalloc_noptr(n * 2 + 1), *p = buf;
 
   while(n-- > 0)
-    p += sprintf(p, "%02x", (unsigned)*ptr++);
+    p += byte_snprintf(p, 3, "%02x", (unsigned)*ptr++);
+  *p = 0;
   return buf;
 }
 
+/** @brief Convert a character to its value as a hex digit
+ * @param c Character code
+ * @return Value has hex digit or -1
+ *
+ * The 'q' stands for 'quiet' - this function does not report errors.
+ */
 int unhexdigitq(int c) {
   switch(c) {
   case '0': return 0;
@@ -58,20 +66,39 @@ int unhexdigitq(int c) {
   }
 }
 
+/** @brief Convert a character to its value as a hex digit
+ * @param c Character code
+ * @return Value has hex digit or -1
+ *
+ * If the character is not a valid hex digit then an error is logged.
+ * See @ref unhexdigitq() if that is a problem.
+ */
 int unhexdigit(int c) {
   int d;
 
-  if((d = unhexdigitq(c)) < 0) error(0, "invalid hex digit");
+  if((d = unhexdigitq(c)) < 0)
+    disorder_error(0, "invalid hex digit");
   return d;
 }
 
+/** @brief Convert a hex string to bytes
+ * @param s Pointer to hex string
+ * @param np Where to store byte string length or NULL
+ * @return Allocated buffer, or 0
+ *
+ * @p s should point to a 0-terminated string containing an even number
+ * of hex digits.  They are converted to bytes and returned via the return
+ * value and optionally the length via @p np.
+ *
+ * On any error a message is logged and a null pointer is returned.
+ */
 uint8_t *unhex(const char *s, size_t *np) {
   size_t l;
   uint8_t *buf, *p;
   int d1, d2;
 
   if((l = strlen(s)) & 1) {
-    error(0, "hex string has odd length");
+    disorder_error(0, "hex string has odd length");
     return 0;
   }
   p = buf = xmalloc_noptr(l / 2);